Laboratory investigations are proposed to define in vitro parameters of cell-mediated immune response to cancer cells enzymatically desialylated with neuraminidase in patients with solid tumors or inbred rats bearing syngeneic tumors. Studies are in progress to define asialyl-mediated immunogenic augmentation of blood lymphocyte immune response in influencing growth of established autochthonous or syngeneic tumors or prevention of metastatic spread.